xref: /dragonfly/contrib/wpa_supplicant/src/eap_common/eap_sim_common.c (revision 3a84a4273475ed07d0ab1c2dfeffdfedef35d9cd)
1 /*
2  * EAP peer/server: EAP-SIM/AKA/AKA' shared routines
3  * Copyright (c) 2004-2008, Jouni Malinen <j@w1.fi>
4  *
5  * This software may be distributed under the terms of the BSD license.
6  * See README for more details.
7  */
8 
9 #include "includes.h"
10 
11 #include "common.h"
12 #include "wpabuf.h"
13 #include "crypto/aes_wrap.h"
14 #include "crypto/crypto.h"
15 #include "crypto/sha1.h"
16 #include "crypto/sha256.h"
17 #include "crypto/random.h"
18 #include "eap_common/eap_defs.h"
19 #include "eap_common/eap_sim_common.h"
20 
21 
eap_sim_prf(const u8 * key,u8 * x,size_t xlen)22 static int eap_sim_prf(const u8 *key, u8 *x, size_t xlen)
23 {
24           return fips186_2_prf(key, EAP_SIM_MK_LEN, x, xlen);
25 }
26 
27 
eap_sim_derive_mk(const u8 * identity,size_t identity_len,const u8 * nonce_mt,u16 selected_version,const u8 * ver_list,size_t ver_list_len,int num_chal,const u8 * kc,u8 * mk)28 void eap_sim_derive_mk(const u8 *identity, size_t identity_len,
29                            const u8 *nonce_mt, u16 selected_version,
30                            const u8 *ver_list, size_t ver_list_len,
31                            int num_chal, const u8 *kc, u8 *mk)
32 {
33           u8 sel_ver[2];
34           const unsigned char *addr[5];
35           size_t len[5];
36 
37           addr[0] = identity;
38           len[0] = identity_len;
39           addr[1] = kc;
40           len[1] = num_chal * EAP_SIM_KC_LEN;
41           addr[2] = nonce_mt;
42           len[2] = EAP_SIM_NONCE_MT_LEN;
43           addr[3] = ver_list;
44           len[3] = ver_list_len;
45           addr[4] = sel_ver;
46           len[4] = 2;
47 
48           WPA_PUT_BE16(sel_ver, selected_version);
49 
50           /* MK = SHA1(Identity|n*Kc|NONCE_MT|Version List|Selected Version) */
51           sha1_vector(5, addr, len, mk);
52           wpa_hexdump_key(MSG_DEBUG, "EAP-SIM: MK", mk, EAP_SIM_MK_LEN);
53 }
54 
55 
eap_aka_derive_mk(const u8 * identity,size_t identity_len,const u8 * ik,const u8 * ck,u8 * mk)56 void eap_aka_derive_mk(const u8 *identity, size_t identity_len,
57                            const u8 *ik, const u8 *ck, u8 *mk)
58 {
59           const u8 *addr[3];
60           size_t len[3];
61 
62           addr[0] = identity;
63           len[0] = identity_len;
64           addr[1] = ik;
65           len[1] = EAP_AKA_IK_LEN;
66           addr[2] = ck;
67           len[2] = EAP_AKA_CK_LEN;
68 
69           /* MK = SHA1(Identity|IK|CK) */
70           sha1_vector(3, addr, len, mk);
71           wpa_hexdump_key(MSG_DEBUG, "EAP-AKA: IK", ik, EAP_AKA_IK_LEN);
72           wpa_hexdump_key(MSG_DEBUG, "EAP-AKA: CK", ck, EAP_AKA_CK_LEN);
73           wpa_hexdump_key(MSG_DEBUG, "EAP-AKA: MK", mk, EAP_SIM_MK_LEN);
74 }
75 
76 
eap_sim_derive_keys(const u8 * mk,u8 * k_encr,u8 * k_aut,u8 * msk,u8 * emsk)77 int eap_sim_derive_keys(const u8 *mk, u8 *k_encr, u8 *k_aut, u8 *msk, u8 *emsk)
78 {
79           u8 buf[EAP_SIM_K_ENCR_LEN + EAP_SIM_K_AUT_LEN +
80                  EAP_SIM_KEYING_DATA_LEN + EAP_EMSK_LEN], *pos;
81           if (eap_sim_prf(mk, buf, sizeof(buf)) < 0) {
82                     wpa_printf(MSG_ERROR, "EAP-SIM: Failed to derive keys");
83                     return -1;
84           }
85           pos = buf;
86           os_memcpy(k_encr, pos, EAP_SIM_K_ENCR_LEN);
87           pos += EAP_SIM_K_ENCR_LEN;
88           os_memcpy(k_aut, pos, EAP_SIM_K_AUT_LEN);
89           pos += EAP_SIM_K_AUT_LEN;
90           os_memcpy(msk, pos, EAP_SIM_KEYING_DATA_LEN);
91           pos += EAP_SIM_KEYING_DATA_LEN;
92           os_memcpy(emsk, pos, EAP_EMSK_LEN);
93 
94           wpa_hexdump_key(MSG_DEBUG, "EAP-SIM: K_encr",
95                               k_encr, EAP_SIM_K_ENCR_LEN);
96           wpa_hexdump_key(MSG_DEBUG, "EAP-SIM: K_aut",
97                               k_aut, EAP_SIM_K_AUT_LEN);
98           wpa_hexdump_key(MSG_DEBUG, "EAP-SIM: keying material (MSK)",
99                               msk, EAP_SIM_KEYING_DATA_LEN);
100           wpa_hexdump_key(MSG_DEBUG, "EAP-SIM: EMSK", emsk, EAP_EMSK_LEN);
101           os_memset(buf, 0, sizeof(buf));
102 
103           return 0;
104 }
105 
106 
eap_sim_derive_keys_reauth(u16 _counter,const u8 * identity,size_t identity_len,const u8 * nonce_s,const u8 * mk,u8 * msk,u8 * emsk)107 int eap_sim_derive_keys_reauth(u16 _counter,
108                                      const u8 *identity, size_t identity_len,
109                                      const u8 *nonce_s, const u8 *mk, u8 *msk,
110                                      u8 *emsk)
111 {
112           u8 xkey[SHA1_MAC_LEN];
113           u8 buf[EAP_SIM_KEYING_DATA_LEN + EAP_EMSK_LEN + 32];
114           u8 counter[2];
115           const u8 *addr[4];
116           size_t len[4];
117 
118           while (identity_len > 0 && identity[identity_len - 1] == 0) {
119                     wpa_printf(MSG_DEBUG, "EAP-SIM: Workaround - drop null "
120                                  "character from the end of identity");
121                     identity_len--;
122           }
123           addr[0] = identity;
124           len[0] = identity_len;
125           addr[1] = counter;
126           len[1] = 2;
127           addr[2] = nonce_s;
128           len[2] = EAP_SIM_NONCE_S_LEN;
129           addr[3] = mk;
130           len[3] = EAP_SIM_MK_LEN;
131 
132           WPA_PUT_BE16(counter, _counter);
133 
134           wpa_printf(MSG_DEBUG, "EAP-SIM: Deriving keying data from reauth");
135           wpa_hexdump_ascii(MSG_DEBUG, "EAP-SIM: Identity",
136                                 identity, identity_len);
137           wpa_hexdump(MSG_DEBUG, "EAP-SIM: counter", counter, 2);
138           wpa_hexdump(MSG_DEBUG, "EAP-SIM: NONCE_S", nonce_s,
139                         EAP_SIM_NONCE_S_LEN);
140           wpa_hexdump_key(MSG_DEBUG, "EAP-SIM: MK", mk, EAP_SIM_MK_LEN);
141 
142           /* XKEY' = SHA1(Identity|counter|NONCE_S|MK) */
143           sha1_vector(4, addr, len, xkey);
144           wpa_hexdump(MSG_DEBUG, "EAP-SIM: XKEY'", xkey, SHA1_MAC_LEN);
145 
146           if (eap_sim_prf(xkey, buf, sizeof(buf)) < 0) {
147                     wpa_printf(MSG_ERROR, "EAP-SIM: Failed to derive keys");
148                     return -1;
149           }
150           if (msk) {
151                     os_memcpy(msk, buf, EAP_SIM_KEYING_DATA_LEN);
152                     wpa_hexdump(MSG_DEBUG, "EAP-SIM: keying material (MSK)",
153                                   msk, EAP_SIM_KEYING_DATA_LEN);
154           }
155           if (emsk) {
156                     os_memcpy(emsk, buf + EAP_SIM_KEYING_DATA_LEN, EAP_EMSK_LEN);
157                     wpa_hexdump(MSG_DEBUG, "EAP-SIM: EMSK", emsk, EAP_EMSK_LEN);
158           }
159           os_memset(buf, 0, sizeof(buf));
160 
161           return 0;
162 }
163 
164 
eap_sim_verify_mac(const u8 * k_aut,const struct wpabuf * req,const u8 * mac,const u8 * extra,size_t extra_len)165 int eap_sim_verify_mac(const u8 *k_aut, const struct wpabuf *req,
166                            const u8 *mac, const u8 *extra, size_t extra_len)
167 {
168           unsigned char hmac[SHA1_MAC_LEN];
169           const u8 *addr[2];
170           size_t len[2];
171           u8 *tmp;
172 
173           if (mac == NULL || wpabuf_len(req) < EAP_SIM_MAC_LEN ||
174               mac < wpabuf_head_u8(req) ||
175               mac > wpabuf_head_u8(req) + wpabuf_len(req) - EAP_SIM_MAC_LEN)
176                     return -1;
177 
178           tmp = os_memdup(wpabuf_head(req), wpabuf_len(req));
179           if (tmp == NULL)
180                     return -1;
181 
182           addr[0] = tmp;
183           len[0] = wpabuf_len(req);
184           addr[1] = extra;
185           len[1] = extra_len;
186 
187           /* HMAC-SHA1-128 */
188           os_memset(tmp + (mac - wpabuf_head_u8(req)), 0, EAP_SIM_MAC_LEN);
189           wpa_hexdump(MSG_MSGDUMP, "EAP-SIM: Verify MAC - msg",
190                         tmp, wpabuf_len(req));
191           wpa_hexdump(MSG_MSGDUMP, "EAP-SIM: Verify MAC - extra data",
192                         extra, extra_len);
193           wpa_hexdump_key(MSG_MSGDUMP, "EAP-SIM: Verify MAC - K_aut",
194                               k_aut, EAP_SIM_K_AUT_LEN);
195           hmac_sha1_vector(k_aut, EAP_SIM_K_AUT_LEN, 2, addr, len, hmac);
196           wpa_hexdump(MSG_MSGDUMP, "EAP-SIM: Verify MAC: MAC",
197                         hmac, EAP_SIM_MAC_LEN);
198           os_free(tmp);
199 
200           return (os_memcmp_const(hmac, mac, EAP_SIM_MAC_LEN) == 0) ? 0 : 1;
201 }
202 
203 
eap_sim_add_mac(const u8 * k_aut,const u8 * msg,size_t msg_len,u8 * mac,const u8 * extra,size_t extra_len)204 void eap_sim_add_mac(const u8 *k_aut, const u8 *msg, size_t msg_len, u8 *mac,
205                          const u8 *extra, size_t extra_len)
206 {
207           unsigned char hmac[SHA1_MAC_LEN];
208           const u8 *addr[2];
209           size_t len[2];
210 
211           addr[0] = msg;
212           len[0] = msg_len;
213           addr[1] = extra;
214           len[1] = extra_len;
215 
216           /* HMAC-SHA1-128 */
217           os_memset(mac, 0, EAP_SIM_MAC_LEN);
218           wpa_hexdump(MSG_MSGDUMP, "EAP-SIM: Add MAC - msg", msg, msg_len);
219           wpa_hexdump(MSG_MSGDUMP, "EAP-SIM: Add MAC - extra data",
220                         extra, extra_len);
221           wpa_hexdump_key(MSG_MSGDUMP, "EAP-SIM: Add MAC - K_aut",
222                               k_aut, EAP_SIM_K_AUT_LEN);
223           hmac_sha1_vector(k_aut, EAP_SIM_K_AUT_LEN, 2, addr, len, hmac);
224           os_memcpy(mac, hmac, EAP_SIM_MAC_LEN);
225           wpa_hexdump(MSG_MSGDUMP, "EAP-SIM: Add MAC: MAC",
226                         mac, EAP_SIM_MAC_LEN);
227 }
228 
229 
230 #if defined(EAP_AKA_PRIME) || defined(EAP_SERVER_AKA_PRIME)
prf_prime(const u8 * k,const char * seed1,const u8 * seed2,size_t seed2_len,const u8 * seed3,size_t seed3_len,u8 * res,size_t res_len)231 static void prf_prime(const u8 *k, const char *seed1,
232                           const u8 *seed2, size_t seed2_len,
233                           const u8 *seed3, size_t seed3_len,
234                           u8 *res, size_t res_len)
235 {
236           const u8 *addr[5];
237           size_t len[5];
238           u8 hash[SHA256_MAC_LEN];
239           u8 iter;
240 
241           /*
242            * PRF'(K,S) = T1 | T2 | T3 | T4 | ...
243            * T1 = HMAC-SHA-256 (K, S | 0x01)
244            * T2 = HMAC-SHA-256 (K, T1 | S | 0x02)
245            * T3 = HMAC-SHA-256 (K, T2 | S | 0x03)
246            * T4 = HMAC-SHA-256 (K, T3 | S | 0x04)
247            * ...
248            */
249 
250           addr[0] = hash;
251           len[0] = 0;
252           addr[1] = (const u8 *) seed1;
253           len[1] = os_strlen(seed1);
254           addr[2] = seed2;
255           len[2] = seed2_len;
256           addr[3] = seed3;
257           len[3] = seed3_len;
258           addr[4] = &iter;
259           len[4] = 1;
260 
261           iter = 0;
262           while (res_len) {
263                     size_t hlen;
264                     iter++;
265                     hmac_sha256_vector(k, 32, 5, addr, len, hash);
266                     len[0] = SHA256_MAC_LEN;
267                     hlen = res_len > SHA256_MAC_LEN ? SHA256_MAC_LEN : res_len;
268                     os_memcpy(res, hash, hlen);
269                     res += hlen;
270                     res_len -= hlen;
271           }
272 }
273 
274 
eap_aka_prime_derive_keys(const u8 * identity,size_t identity_len,const u8 * ik,const u8 * ck,u8 * k_encr,u8 * k_aut,u8 * k_re,u8 * msk,u8 * emsk)275 void eap_aka_prime_derive_keys(const u8 *identity, size_t identity_len,
276                                      const u8 *ik, const u8 *ck, u8 *k_encr,
277                                      u8 *k_aut, u8 *k_re, u8 *msk, u8 *emsk)
278 {
279           u8 key[EAP_AKA_IK_LEN + EAP_AKA_CK_LEN];
280           u8 keys[EAP_SIM_K_ENCR_LEN + EAP_AKA_PRIME_K_AUT_LEN +
281                     EAP_AKA_PRIME_K_RE_LEN + EAP_MSK_LEN + EAP_EMSK_LEN];
282           u8 *pos;
283 
284           /*
285            * MK = PRF'(IK'|CK',"EAP-AKA'"|Identity)
286            * K_encr = MK[0..127]
287            * K_aut  = MK[128..383]
288            * K_re   = MK[384..639]
289            * MSK    = MK[640..1151]
290            * EMSK   = MK[1152..1663]
291            */
292 
293           os_memcpy(key, ik, EAP_AKA_IK_LEN);
294           os_memcpy(key + EAP_AKA_IK_LEN, ck, EAP_AKA_CK_LEN);
295 
296           prf_prime(key, "EAP-AKA'", identity, identity_len, NULL, 0,
297                       keys, sizeof(keys));
298 
299           pos = keys;
300           os_memcpy(k_encr, pos, EAP_SIM_K_ENCR_LEN);
301           wpa_hexdump_key(MSG_DEBUG, "EAP-AKA': K_encr",
302                               k_encr, EAP_SIM_K_ENCR_LEN);
303           pos += EAP_SIM_K_ENCR_LEN;
304 
305           os_memcpy(k_aut, pos, EAP_AKA_PRIME_K_AUT_LEN);
306           wpa_hexdump_key(MSG_DEBUG, "EAP-AKA': K_aut",
307                               k_aut, EAP_AKA_PRIME_K_AUT_LEN);
308           pos += EAP_AKA_PRIME_K_AUT_LEN;
309 
310           os_memcpy(k_re, pos, EAP_AKA_PRIME_K_RE_LEN);
311           wpa_hexdump_key(MSG_DEBUG, "EAP-AKA': K_re",
312                               k_re, EAP_AKA_PRIME_K_RE_LEN);
313           pos += EAP_AKA_PRIME_K_RE_LEN;
314 
315           os_memcpy(msk, pos, EAP_MSK_LEN);
316           wpa_hexdump_key(MSG_DEBUG, "EAP-AKA': MSK", msk, EAP_MSK_LEN);
317           pos += EAP_MSK_LEN;
318 
319           os_memcpy(emsk, pos, EAP_EMSK_LEN);
320           wpa_hexdump_key(MSG_DEBUG, "EAP-AKA': EMSK", emsk, EAP_EMSK_LEN);
321 }
322 
323 
eap_aka_prime_derive_keys_reauth(const u8 * k_re,u16 counter,const u8 * identity,size_t identity_len,const u8 * nonce_s,u8 * msk,u8 * emsk)324 int eap_aka_prime_derive_keys_reauth(const u8 *k_re, u16 counter,
325                                              const u8 *identity, size_t identity_len,
326                                              const u8 *nonce_s, u8 *msk, u8 *emsk)
327 {
328           u8 seed3[2 + EAP_SIM_NONCE_S_LEN];
329           u8 keys[EAP_MSK_LEN + EAP_EMSK_LEN];
330           u8 *pos;
331 
332           /*
333            * MK = PRF'(K_re,"EAP-AKA' re-auth"|Identity|counter|NONCE_S)
334            * MSK  = MK[0..511]
335            * EMSK = MK[512..1023]
336            */
337 
338           WPA_PUT_BE16(seed3, counter);
339           os_memcpy(seed3 + 2, nonce_s, EAP_SIM_NONCE_S_LEN);
340 
341           prf_prime(k_re, "EAP-AKA' re-auth", identity, identity_len,
342                       seed3, sizeof(seed3),
343                       keys, sizeof(keys));
344 
345           pos = keys;
346           os_memcpy(msk, pos, EAP_MSK_LEN);
347           wpa_hexdump_key(MSG_DEBUG, "EAP-AKA': MSK", msk, EAP_MSK_LEN);
348           pos += EAP_MSK_LEN;
349 
350           os_memcpy(emsk, pos, EAP_EMSK_LEN);
351           wpa_hexdump_key(MSG_DEBUG, "EAP-AKA': EMSK", emsk, EAP_EMSK_LEN);
352 
353           os_memset(keys, 0, sizeof(keys));
354 
355           return 0;
356 }
357 
358 
eap_sim_verify_mac_sha256(const u8 * k_aut,const struct wpabuf * req,const u8 * mac,const u8 * extra,size_t extra_len)359 int eap_sim_verify_mac_sha256(const u8 *k_aut, const struct wpabuf *req,
360                                     const u8 *mac, const u8 *extra, size_t extra_len)
361 {
362           unsigned char hmac[SHA256_MAC_LEN];
363           const u8 *addr[2];
364           size_t len[2];
365           u8 *tmp;
366 
367           if (mac == NULL || wpabuf_len(req) < EAP_SIM_MAC_LEN ||
368               mac < wpabuf_head_u8(req) ||
369               mac > wpabuf_head_u8(req) + wpabuf_len(req) - EAP_SIM_MAC_LEN)
370                     return -1;
371 
372           tmp = os_memdup(wpabuf_head(req), wpabuf_len(req));
373           if (tmp == NULL)
374                     return -1;
375 
376           addr[0] = tmp;
377           len[0] = wpabuf_len(req);
378           addr[1] = extra;
379           len[1] = extra_len;
380 
381           /* HMAC-SHA-256-128 */
382           os_memset(tmp + (mac - wpabuf_head_u8(req)), 0, EAP_SIM_MAC_LEN);
383           wpa_hexdump(MSG_MSGDUMP, "EAP-AKA': Verify MAC - msg",
384                         tmp, wpabuf_len(req));
385           wpa_hexdump(MSG_MSGDUMP, "EAP-AKA': Verify MAC - extra data",
386                         extra, extra_len);
387           wpa_hexdump_key(MSG_MSGDUMP, "EAP-AKA': Verify MAC - K_aut",
388                               k_aut, EAP_AKA_PRIME_K_AUT_LEN);
389           hmac_sha256_vector(k_aut, EAP_AKA_PRIME_K_AUT_LEN, 2, addr, len, hmac);
390           wpa_hexdump(MSG_MSGDUMP, "EAP-AKA': Verify MAC: MAC",
391                         hmac, EAP_SIM_MAC_LEN);
392           os_free(tmp);
393 
394           return (os_memcmp_const(hmac, mac, EAP_SIM_MAC_LEN) == 0) ? 0 : 1;
395 }
396 
397 
eap_sim_add_mac_sha256(const u8 * k_aut,const u8 * msg,size_t msg_len,u8 * mac,const u8 * extra,size_t extra_len)398 void eap_sim_add_mac_sha256(const u8 *k_aut, const u8 *msg, size_t msg_len,
399                                   u8 *mac, const u8 *extra, size_t extra_len)
400 {
401           unsigned char hmac[SHA256_MAC_LEN];
402           const u8 *addr[2];
403           size_t len[2];
404 
405           addr[0] = msg;
406           len[0] = msg_len;
407           addr[1] = extra;
408           len[1] = extra_len;
409 
410           /* HMAC-SHA-256-128 */
411           os_memset(mac, 0, EAP_SIM_MAC_LEN);
412           wpa_hexdump(MSG_MSGDUMP, "EAP-AKA': Add MAC - msg", msg, msg_len);
413           wpa_hexdump(MSG_MSGDUMP, "EAP-AKA': Add MAC - extra data",
414                         extra, extra_len);
415           wpa_hexdump_key(MSG_MSGDUMP, "EAP-AKA': Add MAC - K_aut",
416                               k_aut, EAP_AKA_PRIME_K_AUT_LEN);
417           hmac_sha256_vector(k_aut, EAP_AKA_PRIME_K_AUT_LEN, 2, addr, len, hmac);
418           os_memcpy(mac, hmac, EAP_SIM_MAC_LEN);
419           wpa_hexdump(MSG_MSGDUMP, "EAP-AKA': Add MAC: MAC",
420                         mac, EAP_SIM_MAC_LEN);
421 }
422 
423 
eap_aka_prime_derive_ck_ik_prime(u8 * ck,u8 * ik,const u8 * sqn_ak,const u8 * network_name,size_t network_name_len)424 void eap_aka_prime_derive_ck_ik_prime(u8 *ck, u8 *ik, const u8 *sqn_ak,
425                                               const u8 *network_name,
426                                               size_t network_name_len)
427 {
428           u8 key[EAP_AKA_CK_LEN + EAP_AKA_IK_LEN];
429           u8 hash[SHA256_MAC_LEN];
430           const u8 *addr[5];
431           size_t len[5];
432           u8 fc;
433           u8 l0[2], l1[2];
434 
435           /* 3GPP TS 33.402 V8.0.0
436            * (CK', IK') = F(CK, IK, <access network identity>)
437            */
438           /* TODO: CK', IK' generation should really be moved into the actual
439            * AKA procedure with network name passed in there and option to use
440            * AMF separation bit = 1 (3GPP TS 33.401). */
441 
442           /* Change Request 33.402 CR 0033 to version 8.1.1 from
443            * 3GPP TSG-SA WG3 Meeting #53 in September 2008:
444            *
445            * CK' || IK' = HMAC-SHA-256(Key, S)
446            * S = FC || P0 || L0 || P1 || L1 || ... || Pn || Ln
447            * Key = CK || IK
448            * FC = 0x20
449            * P0 = access network identity (3GPP TS 24.302)
450            * L0 = length of acceess network identity (2 octets, big endian)
451            * P1 = SQN xor AK (if AK is not used, AK is treaded as 000..0
452            * L1 = 0x00 0x06
453            */
454 
455           fc = 0x20;
456 
457           wpa_printf(MSG_DEBUG, "EAP-AKA': Derive (CK',IK') from (CK,IK)");
458           wpa_hexdump_key(MSG_DEBUG, "EAP-AKA': CK", ck, EAP_AKA_CK_LEN);
459           wpa_hexdump_key(MSG_DEBUG, "EAP-AKA': IK", ik, EAP_AKA_IK_LEN);
460           wpa_printf(MSG_DEBUG, "EAP-AKA': FC = 0x%x", fc);
461           wpa_hexdump_ascii(MSG_DEBUG, "EAP-AKA': P0 = Access network identity",
462                                 network_name, network_name_len);
463           wpa_hexdump(MSG_DEBUG, "EAP-AKA': P1 = SQN xor AK", sqn_ak, 6);
464 
465           os_memcpy(key, ck, EAP_AKA_CK_LEN);
466           os_memcpy(key + EAP_AKA_CK_LEN, ik, EAP_AKA_IK_LEN);
467           wpa_hexdump_key(MSG_DEBUG, "EAP-AKA': Key = CK || IK",
468                               key, sizeof(key));
469 
470           addr[0] = &fc;
471           len[0] = 1;
472           addr[1] = network_name;
473           len[1] = network_name_len;
474           WPA_PUT_BE16(l0, network_name_len);
475           addr[2] = l0;
476           len[2] = 2;
477           addr[3] = sqn_ak;
478           len[3] = 6;
479           WPA_PUT_BE16(l1, 6);
480           addr[4] = l1;
481           len[4] = 2;
482 
483           hmac_sha256_vector(key, sizeof(key), 5, addr, len, hash);
484           wpa_hexdump_key(MSG_DEBUG, "EAP-AKA': KDF output (CK' || IK')",
485                               hash, sizeof(hash));
486 
487           os_memcpy(ck, hash, EAP_AKA_CK_LEN);
488           os_memcpy(ik, hash + EAP_AKA_CK_LEN, EAP_AKA_IK_LEN);
489           wpa_hexdump_key(MSG_DEBUG, "EAP-AKA': CK'", ck, EAP_AKA_CK_LEN);
490           wpa_hexdump_key(MSG_DEBUG, "EAP-AKA': IK'", ik, EAP_AKA_IK_LEN);
491 }
492 #endif /* EAP_AKA_PRIME || EAP_SERVER_AKA_PRIME */
493 
494 
eap_sim_parse_attr(const u8 * start,const u8 * end,struct eap_sim_attrs * attr,int aka,int encr)495 int eap_sim_parse_attr(const u8 *start, const u8 *end,
496                            struct eap_sim_attrs *attr, int aka, int encr)
497 {
498           const u8 *pos = start, *apos;
499           size_t alen, plen, i, list_len;
500 
501           os_memset(attr, 0, sizeof(*attr));
502           attr->id_req = NO_ID_REQ;
503           attr->notification = -1;
504           attr->counter = -1;
505           attr->selected_version = -1;
506           attr->client_error_code = -1;
507 
508           while (pos < end) {
509                     if (pos + 2 > end) {
510                               wpa_printf(MSG_INFO, "EAP-SIM: Attribute overflow(1)");
511                               return -1;
512                     }
513                     wpa_printf(MSG_MSGDUMP, "EAP-SIM: Attribute: Type=%d Len=%d",
514                                  pos[0], pos[1] * 4);
515                     if (pos + pos[1] * 4 > end) {
516                               wpa_printf(MSG_INFO, "EAP-SIM: Attribute overflow "
517                                            "(pos=%p len=%d end=%p)",
518                                            pos, pos[1] * 4, end);
519                               return -1;
520                     }
521                     if (pos[1] == 0) {
522                               wpa_printf(MSG_INFO, "EAP-SIM: Attribute underflow");
523                               return -1;
524                     }
525                     apos = pos + 2;
526                     alen = pos[1] * 4 - 2;
527                     wpa_hexdump(MSG_MSGDUMP, "EAP-SIM: Attribute data",
528                                   apos, alen);
529 
530                     switch (pos[0]) {
531                     case EAP_SIM_AT_RAND:
532                               wpa_printf(MSG_DEBUG, "EAP-SIM: AT_RAND");
533                               apos += 2;
534                               alen -= 2;
535                               if ((!aka && (alen % GSM_RAND_LEN)) ||
536                                   (aka && alen != EAP_AKA_RAND_LEN)) {
537                                         wpa_printf(MSG_INFO, "EAP-SIM: Invalid AT_RAND"
538                                                      " (len %lu)",
539                                                      (unsigned long) alen);
540                                         return -1;
541                               }
542                               attr->rand = apos;
543                               attr->num_chal = alen / GSM_RAND_LEN;
544                               break;
545                     case EAP_SIM_AT_AUTN:
546                               wpa_printf(MSG_DEBUG, "EAP-AKA: AT_AUTN");
547                               if (!aka) {
548                                         wpa_printf(MSG_DEBUG, "EAP-SIM: "
549                                                      "Unexpected AT_AUTN");
550                                         return -1;
551                               }
552                               apos += 2;
553                               alen -= 2;
554                               if (alen != EAP_AKA_AUTN_LEN) {
555                                         wpa_printf(MSG_INFO, "EAP-AKA: Invalid AT_AUTN"
556                                                      " (len %lu)",
557                                                      (unsigned long) alen);
558                                         return -1;
559                               }
560                               attr->autn = apos;
561                               break;
562                     case EAP_SIM_AT_PADDING:
563                               if (!encr) {
564                                         wpa_printf(MSG_ERROR, "EAP-SIM: Unencrypted "
565                                                      "AT_PADDING");
566                                         return -1;
567                               }
568                               wpa_printf(MSG_DEBUG, "EAP-SIM: (encr) AT_PADDING");
569                               for (i = 2; i < alen; i++) {
570                                         if (apos[i] != 0) {
571                                                   wpa_printf(MSG_INFO, "EAP-SIM: (encr) "
572                                                                "AT_PADDING used a non-zero"
573                                                                " padding byte");
574                                                   wpa_hexdump(MSG_DEBUG, "EAP-SIM: "
575                                                                 "(encr) padding bytes",
576                                                                 apos + 2, alen - 2);
577                                                   return -1;
578                                         }
579                               }
580                               break;
581                     case EAP_SIM_AT_NONCE_MT:
582                               wpa_printf(MSG_DEBUG, "EAP-SIM: AT_NONCE_MT");
583                               if (alen != 2 + EAP_SIM_NONCE_MT_LEN) {
584                                         wpa_printf(MSG_INFO, "EAP-SIM: Invalid "
585                                                      "AT_NONCE_MT length");
586                                         return -1;
587                               }
588                               attr->nonce_mt = apos + 2;
589                               break;
590                     case EAP_SIM_AT_PERMANENT_ID_REQ:
591                               wpa_printf(MSG_DEBUG, "EAP-SIM: AT_PERMANENT_ID_REQ");
592                               attr->id_req = PERMANENT_ID;
593                               break;
594                     case EAP_SIM_AT_MAC:
595                               wpa_printf(MSG_DEBUG, "EAP-SIM: AT_MAC");
596                               if (alen != 2 + EAP_SIM_MAC_LEN) {
597                                         wpa_printf(MSG_INFO, "EAP-SIM: Invalid AT_MAC "
598                                                      "length");
599                                         return -1;
600                               }
601                               attr->mac = apos + 2;
602                               break;
603                     case EAP_SIM_AT_NOTIFICATION:
604                               if (alen != 2) {
605                                         wpa_printf(MSG_INFO, "EAP-SIM: Invalid "
606                                                      "AT_NOTIFICATION length %lu",
607                                                      (unsigned long) alen);
608                                         return -1;
609                               }
610                               attr->notification = apos[0] * 256 + apos[1];
611                               wpa_printf(MSG_DEBUG, "EAP-SIM: AT_NOTIFICATION %d",
612                                            attr->notification);
613                               break;
614                     case EAP_SIM_AT_ANY_ID_REQ:
615                               wpa_printf(MSG_DEBUG, "EAP-SIM: AT_ANY_ID_REQ");
616                               attr->id_req = ANY_ID;
617                               break;
618                     case EAP_SIM_AT_IDENTITY:
619                               wpa_printf(MSG_DEBUG, "EAP-SIM: AT_IDENTITY");
620                               plen = WPA_GET_BE16(apos);
621                               apos += 2;
622                               alen -= 2;
623                               if (plen > alen) {
624                                         wpa_printf(MSG_INFO, "EAP-SIM: Invalid "
625                                                      "AT_IDENTITY (Actual Length %lu, "
626                                                      "remaining length %lu)",
627                                                      (unsigned long) plen,
628                                                      (unsigned long) alen);
629                                         return -1;
630                               }
631 
632                               attr->identity = apos;
633                               attr->identity_len = plen;
634                               break;
635                     case EAP_SIM_AT_VERSION_LIST:
636                               if (aka) {
637                                         wpa_printf(MSG_DEBUG, "EAP-AKA: "
638                                                      "Unexpected AT_VERSION_LIST");
639                                         return -1;
640                               }
641                               list_len = apos[0] * 256 + apos[1];
642                               wpa_printf(MSG_DEBUG, "EAP-SIM: AT_VERSION_LIST");
643                               if (list_len < 2 || list_len > alen - 2) {
644                                         wpa_printf(MSG_WARNING, "EAP-SIM: Invalid "
645                                                      "AT_VERSION_LIST (list_len=%lu "
646                                                      "attr_len=%lu)",
647                                                      (unsigned long) list_len,
648                                                      (unsigned long) alen);
649                                         return -1;
650                               }
651                               attr->version_list = apos + 2;
652                               attr->version_list_len = list_len;
653                               break;
654                     case EAP_SIM_AT_SELECTED_VERSION:
655                               wpa_printf(MSG_DEBUG, "EAP-SIM: AT_SELECTED_VERSION");
656                               if (alen != 2) {
657                                         wpa_printf(MSG_INFO, "EAP-SIM: Invalid "
658                                                      "AT_SELECTED_VERSION length %lu",
659                                                      (unsigned long) alen);
660                                         return -1;
661                               }
662                               attr->selected_version = apos[0] * 256 + apos[1];
663                               wpa_printf(MSG_DEBUG, "EAP-SIM: AT_SELECTED_VERSION "
664                                            "%d", attr->selected_version);
665                               break;
666                     case EAP_SIM_AT_FULLAUTH_ID_REQ:
667                               wpa_printf(MSG_DEBUG, "EAP-SIM: AT_FULLAUTH_ID_REQ");
668                               attr->id_req = FULLAUTH_ID;
669                               break;
670                     case EAP_SIM_AT_COUNTER:
671                               if (!encr) {
672                                         wpa_printf(MSG_ERROR, "EAP-SIM: Unencrypted "
673                                                      "AT_COUNTER");
674                                         return -1;
675                               }
676                               if (alen != 2) {
677                                         wpa_printf(MSG_INFO, "EAP-SIM: (encr) Invalid "
678                                                      "AT_COUNTER (alen=%lu)",
679                                                      (unsigned long) alen);
680                                         return -1;
681                               }
682                               attr->counter = apos[0] * 256 + apos[1];
683                               wpa_printf(MSG_DEBUG, "EAP-SIM: (encr) AT_COUNTER %d",
684                                            attr->counter);
685                               break;
686                     case EAP_SIM_AT_COUNTER_TOO_SMALL:
687                               if (!encr) {
688                                         wpa_printf(MSG_ERROR, "EAP-SIM: Unencrypted "
689                                                      "AT_COUNTER_TOO_SMALL");
690                                         return -1;
691                               }
692                               if (alen != 2) {
693                                         wpa_printf(MSG_INFO, "EAP-SIM: (encr) Invalid "
694                                                      "AT_COUNTER_TOO_SMALL (alen=%lu)",
695                                                      (unsigned long) alen);
696                                         return -1;
697                               }
698                               wpa_printf(MSG_DEBUG, "EAP-SIM: (encr) "
699                                            "AT_COUNTER_TOO_SMALL");
700                               attr->counter_too_small = 1;
701                               break;
702                     case EAP_SIM_AT_NONCE_S:
703                               if (!encr) {
704                                         wpa_printf(MSG_ERROR, "EAP-SIM: Unencrypted "
705                                                      "AT_NONCE_S");
706                                         return -1;
707                               }
708                               wpa_printf(MSG_DEBUG, "EAP-SIM: (encr) "
709                                            "AT_NONCE_S");
710                               if (alen != 2 + EAP_SIM_NONCE_S_LEN) {
711                                         wpa_printf(MSG_INFO, "EAP-SIM: (encr) Invalid "
712                                                      "AT_NONCE_S (alen=%lu)",
713                                                      (unsigned long) alen);
714                                         return -1;
715                               }
716                               attr->nonce_s = apos + 2;
717                               break;
718                     case EAP_SIM_AT_CLIENT_ERROR_CODE:
719                               if (alen != 2) {
720                                         wpa_printf(MSG_INFO, "EAP-SIM: Invalid "
721                                                      "AT_CLIENT_ERROR_CODE length %lu",
722                                                      (unsigned long) alen);
723                                         return -1;
724                               }
725                               attr->client_error_code = apos[0] * 256 + apos[1];
726                               wpa_printf(MSG_DEBUG, "EAP-SIM: AT_CLIENT_ERROR_CODE "
727                                            "%d", attr->client_error_code);
728                               break;
729                     case EAP_SIM_AT_IV:
730                               wpa_printf(MSG_DEBUG, "EAP-SIM: AT_IV");
731                               if (alen != 2 + EAP_SIM_MAC_LEN) {
732                                         wpa_printf(MSG_INFO, "EAP-SIM: Invalid AT_IV "
733                                                      "length %lu", (unsigned long) alen);
734                                         return -1;
735                               }
736                               attr->iv = apos + 2;
737                               break;
738                     case EAP_SIM_AT_ENCR_DATA:
739                               wpa_printf(MSG_DEBUG, "EAP-SIM: AT_ENCR_DATA");
740                               attr->encr_data = apos + 2;
741                               attr->encr_data_len = alen - 2;
742                               if (attr->encr_data_len % 16) {
743                                         wpa_printf(MSG_INFO, "EAP-SIM: Invalid "
744                                                      "AT_ENCR_DATA length %lu",
745                                                      (unsigned long)
746                                                      attr->encr_data_len);
747                                         return -1;
748                               }
749                               break;
750                     case EAP_SIM_AT_NEXT_PSEUDONYM:
751                               if (!encr) {
752                                         wpa_printf(MSG_ERROR, "EAP-SIM: Unencrypted "
753                                                      "AT_NEXT_PSEUDONYM");
754                                         return -1;
755                               }
756                               wpa_printf(MSG_DEBUG, "EAP-SIM: (encr) "
757                                            "AT_NEXT_PSEUDONYM");
758                               plen = apos[0] * 256 + apos[1];
759                               if (plen > alen - 2) {
760                                         wpa_printf(MSG_INFO, "EAP-SIM: (encr) Invalid"
761                                                      " AT_NEXT_PSEUDONYM (actual"
762                                                      " len %lu, attr len %lu)",
763                                                      (unsigned long) plen,
764                                                      (unsigned long) alen);
765                                         return -1;
766                               }
767                               attr->next_pseudonym = pos + 4;
768                               attr->next_pseudonym_len = plen;
769                               break;
770                     case EAP_SIM_AT_NEXT_REAUTH_ID:
771                               if (!encr) {
772                                         wpa_printf(MSG_ERROR, "EAP-SIM: Unencrypted "
773                                                      "AT_NEXT_REAUTH_ID");
774                                         return -1;
775                               }
776                               wpa_printf(MSG_DEBUG, "EAP-SIM: (encr) "
777                                            "AT_NEXT_REAUTH_ID");
778                               plen = apos[0] * 256 + apos[1];
779                               if (plen > alen - 2) {
780                                         wpa_printf(MSG_INFO, "EAP-SIM: (encr) Invalid"
781                                                      " AT_NEXT_REAUTH_ID (actual"
782                                                      " len %lu, attr len %lu)",
783                                                      (unsigned long) plen,
784                                                      (unsigned long) alen);
785                                         return -1;
786                               }
787                               attr->next_reauth_id = pos + 4;
788                               attr->next_reauth_id_len = plen;
789                               break;
790                     case EAP_SIM_AT_RES:
791                               wpa_printf(MSG_DEBUG, "EAP-SIM: AT_RES");
792                               attr->res_len_bits = WPA_GET_BE16(apos);
793                               apos += 2;
794                               alen -= 2;
795                               if (!aka || alen < EAP_AKA_MIN_RES_LEN ||
796                                   alen > EAP_AKA_MAX_RES_LEN) {
797                                         wpa_printf(MSG_INFO, "EAP-SIM: Invalid AT_RES "
798                                                      "(len %lu)",
799                                                      (unsigned long) alen);
800                                         return -1;
801                               }
802                               attr->res = apos;
803                               attr->res_len = alen;
804                               break;
805                     case EAP_SIM_AT_AUTS:
806                               wpa_printf(MSG_DEBUG, "EAP-AKA: AT_AUTS");
807                               if (!aka) {
808                                         wpa_printf(MSG_DEBUG, "EAP-SIM: "
809                                                      "Unexpected AT_AUTS");
810                                         return -1;
811                               }
812                               if (alen != EAP_AKA_AUTS_LEN) {
813                                         wpa_printf(MSG_INFO, "EAP-AKA: Invalid AT_AUTS"
814                                                      " (len %lu)",
815                                                      (unsigned long) alen);
816                                         return -1;
817                               }
818                               attr->auts = apos;
819                               break;
820                     case EAP_SIM_AT_CHECKCODE:
821                               wpa_printf(MSG_DEBUG, "EAP-AKA: AT_CHECKCODE");
822                               if (!aka) {
823                                         wpa_printf(MSG_DEBUG, "EAP-SIM: "
824                                                      "Unexpected AT_CHECKCODE");
825                                         return -1;
826                               }
827                               apos += 2;
828                               alen -= 2;
829                               if (alen != 0 && alen != EAP_AKA_CHECKCODE_LEN &&
830                                   alen != EAP_AKA_PRIME_CHECKCODE_LEN) {
831                                         wpa_printf(MSG_INFO, "EAP-AKA: Invalid "
832                                                      "AT_CHECKCODE (len %lu)",
833                                                      (unsigned long) alen);
834                                         return -1;
835                               }
836                               attr->checkcode = apos;
837                               attr->checkcode_len = alen;
838                               break;
839                     case EAP_SIM_AT_RESULT_IND:
840                               if (encr) {
841                                         wpa_printf(MSG_ERROR, "EAP-SIM: Encrypted "
842                                                      "AT_RESULT_IND");
843                                         return -1;
844                               }
845                               if (alen != 2) {
846                                         wpa_printf(MSG_INFO, "EAP-SIM: Invalid "
847                                                      "AT_RESULT_IND (alen=%lu)",
848                                                      (unsigned long) alen);
849                                         return -1;
850                               }
851                               wpa_printf(MSG_DEBUG, "EAP-SIM: AT_RESULT_IND");
852                               attr->result_ind = 1;
853                               break;
854 #if defined(EAP_AKA_PRIME) || defined(EAP_SERVER_AKA_PRIME)
855                     case EAP_SIM_AT_KDF_INPUT:
856                               if (aka != 2) {
857                                         wpa_printf(MSG_INFO, "EAP-AKA: Unexpected "
858                                                      "AT_KDF_INPUT");
859                                         return -1;
860                               }
861 
862                               wpa_printf(MSG_DEBUG, "EAP-AKA: AT_KDF_INPUT");
863                               plen = WPA_GET_BE16(apos);
864                               apos += 2;
865                               alen -= 2;
866                               if (plen > alen) {
867                                         wpa_printf(MSG_INFO, "EAP-AKA': Invalid "
868                                                      "AT_KDF_INPUT (Actual Length %lu, "
869                                                      "remaining length %lu)",
870                                                      (unsigned long) plen,
871                                                      (unsigned long) alen);
872                                         return -1;
873                               }
874                               attr->kdf_input = apos;
875                               attr->kdf_input_len = plen;
876                               break;
877                     case EAP_SIM_AT_KDF:
878                               if (aka != 2) {
879                                         wpa_printf(MSG_INFO, "EAP-AKA: Unexpected "
880                                                      "AT_KDF");
881                                         return -1;
882                               }
883 
884                               wpa_printf(MSG_DEBUG, "EAP-AKA: AT_KDF");
885                               if (alen != 2) {
886                                         wpa_printf(MSG_INFO, "EAP-AKA': Invalid "
887                                                      "AT_KDF (len %lu)",
888                                                      (unsigned long) alen);
889                                         return -1;
890                               }
891                               if (attr->kdf_count == EAP_AKA_PRIME_KDF_MAX) {
892                                         wpa_printf(MSG_DEBUG, "EAP-AKA': Too many "
893                                                      "AT_KDF attributes - ignore this");
894                                         break;
895                               }
896                               attr->kdf[attr->kdf_count] = WPA_GET_BE16(apos);
897                               attr->kdf_count++;
898                               break;
899                     case EAP_SIM_AT_BIDDING:
900                               wpa_printf(MSG_DEBUG, "EAP-AKA: AT_BIDDING");
901                               if (alen != 2) {
902                                         wpa_printf(MSG_INFO, "EAP-AKA: Invalid "
903                                                      "AT_BIDDING (len %lu)",
904                                                      (unsigned long) alen);
905                                         return -1;
906                               }
907                               attr->bidding = apos;
908                               break;
909 #endif /* EAP_AKA_PRIME || EAP_SERVER_AKA_PRIME */
910                     default:
911                               if (pos[0] < 128) {
912                                         wpa_printf(MSG_INFO, "EAP-SIM: Unrecognized "
913                                                      "non-skippable attribute %d",
914                                                      pos[0]);
915                                         return -1;
916                               }
917 
918                               wpa_printf(MSG_DEBUG, "EAP-SIM: Unrecognized skippable"
919                                            " attribute %d ignored", pos[0]);
920                               break;
921                     }
922 
923                     pos += pos[1] * 4;
924           }
925 
926           wpa_printf(MSG_DEBUG, "EAP-SIM: Attributes parsed successfully "
927                        "(aka=%d encr=%d)", aka, encr);
928 
929           return 0;
930 }
931 
932 
eap_sim_parse_encr(const u8 * k_encr,const u8 * encr_data,size_t encr_data_len,const u8 * iv,struct eap_sim_attrs * attr,int aka)933 u8 * eap_sim_parse_encr(const u8 *k_encr, const u8 *encr_data,
934                               size_t encr_data_len, const u8 *iv,
935                               struct eap_sim_attrs *attr, int aka)
936 {
937           u8 *decrypted;
938 
939           if (!iv) {
940                     wpa_printf(MSG_INFO, "EAP-SIM: Encrypted data, but no IV");
941                     return NULL;
942           }
943 
944           decrypted = os_memdup(encr_data, encr_data_len);
945           if (decrypted == NULL)
946                     return NULL;
947 
948 #ifdef TEST_FUZZ
949                     wpa_printf(MSG_INFO,
950                                  "TEST: Skip AES-128-CBC decryption for fuzz testing");
951 #else /* TEST_FUZZ */
952           if (aes_128_cbc_decrypt(k_encr, iv, decrypted, encr_data_len)) {
953                     os_free(decrypted);
954                     return NULL;
955           }
956 #endif /* TEST_FUZZ */
957           wpa_hexdump(MSG_MSGDUMP, "EAP-SIM: Decrypted AT_ENCR_DATA",
958                         decrypted, encr_data_len);
959 
960           if (eap_sim_parse_attr(decrypted, decrypted + encr_data_len, attr,
961                                      aka, 1)) {
962                     wpa_printf(MSG_INFO, "EAP-SIM: (encr) Failed to parse "
963                                  "decrypted AT_ENCR_DATA");
964                     os_free(decrypted);
965                     return NULL;
966           }
967 
968           return decrypted;
969 }
970 
971 
972 #define EAP_SIM_INIT_LEN 128
973 
974 struct eap_sim_msg {
975           struct wpabuf *buf;
976           size_t mac, iv, encr; /* index from buf */
977 };
978 
979 
eap_sim_msg_init(int code,int id,int type,int subtype)980 struct eap_sim_msg * eap_sim_msg_init(int code, int id, int type, int subtype)
981 {
982           struct eap_sim_msg *msg;
983           struct eap_hdr *eap;
984           u8 *pos;
985 
986           msg = os_zalloc(sizeof(*msg));
987           if (msg == NULL)
988                     return NULL;
989 
990           msg->buf = wpabuf_alloc(EAP_SIM_INIT_LEN);
991           if (msg->buf == NULL) {
992                     os_free(msg);
993                     return NULL;
994           }
995           eap = wpabuf_put(msg->buf, sizeof(*eap));
996           eap->code = code;
997           eap->identifier = id;
998 
999           pos = wpabuf_put(msg->buf, 4);
1000           *pos++ = type;
1001           *pos++ = subtype;
1002           *pos++ = 0; /* Reserved */
1003           *pos++ = 0; /* Reserved */
1004 
1005           return msg;
1006 }
1007 
1008 
eap_sim_msg_finish(struct eap_sim_msg * msg,int type,const u8 * k_aut,const u8 * extra,size_t extra_len)1009 struct wpabuf * eap_sim_msg_finish(struct eap_sim_msg *msg, int type,
1010                                            const u8 *k_aut,
1011                                            const u8 *extra, size_t extra_len)
1012 {
1013           struct eap_hdr *eap;
1014           struct wpabuf *buf;
1015 
1016           if (msg == NULL)
1017                     return NULL;
1018 
1019           eap = wpabuf_mhead(msg->buf);
1020           eap->length = host_to_be16(wpabuf_len(msg->buf));
1021 
1022 #if defined(EAP_AKA_PRIME) || defined(EAP_SERVER_AKA_PRIME)
1023           if (k_aut && msg->mac && type == EAP_TYPE_AKA_PRIME) {
1024                     eap_sim_add_mac_sha256(k_aut, (u8 *) wpabuf_head(msg->buf),
1025                                                wpabuf_len(msg->buf),
1026                                                (u8 *) wpabuf_mhead(msg->buf) +
1027                                                msg->mac, extra, extra_len);
1028           } else
1029 #endif /* EAP_AKA_PRIME || EAP_SERVER_AKA_PRIME */
1030           if (k_aut && msg->mac) {
1031                     eap_sim_add_mac(k_aut, (u8 *) wpabuf_head(msg->buf),
1032                                         wpabuf_len(msg->buf),
1033                                         (u8 *) wpabuf_mhead(msg->buf) + msg->mac,
1034                                         extra, extra_len);
1035           }
1036 
1037           buf = msg->buf;
1038           os_free(msg);
1039           return buf;
1040 }
1041 
1042 
eap_sim_msg_free(struct eap_sim_msg * msg)1043 void eap_sim_msg_free(struct eap_sim_msg *msg)
1044 {
1045           if (msg) {
1046                     wpabuf_free(msg->buf);
1047                     os_free(msg);
1048           }
1049 }
1050 
1051 
eap_sim_msg_add_full(struct eap_sim_msg * msg,u8 attr,const u8 * data,size_t len)1052 u8 * eap_sim_msg_add_full(struct eap_sim_msg *msg, u8 attr,
1053                                 const u8 *data, size_t len)
1054 {
1055           int attr_len = 2 + len;
1056           int pad_len;
1057           u8 *start;
1058 
1059           if (msg == NULL)
1060                     return NULL;
1061 
1062           pad_len = (4 - attr_len % 4) % 4;
1063           attr_len += pad_len;
1064           if (wpabuf_resize(&msg->buf, attr_len))
1065                     return NULL;
1066           start = wpabuf_put(msg->buf, 0);
1067           wpabuf_put_u8(msg->buf, attr);
1068           wpabuf_put_u8(msg->buf, attr_len / 4);
1069           wpabuf_put_data(msg->buf, data, len);
1070           if (pad_len)
1071                     os_memset(wpabuf_put(msg->buf, pad_len), 0, pad_len);
1072           return start;
1073 }
1074 
1075 
eap_sim_msg_add(struct eap_sim_msg * msg,u8 attr,u16 value,const u8 * data,size_t len)1076 u8 * eap_sim_msg_add(struct eap_sim_msg *msg, u8 attr, u16 value,
1077                          const u8 *data, size_t len)
1078 {
1079           int attr_len = 4 + len;
1080           int pad_len;
1081           u8 *start;
1082 
1083           if (msg == NULL)
1084                     return NULL;
1085 
1086           pad_len = (4 - attr_len % 4) % 4;
1087           attr_len += pad_len;
1088           if (wpabuf_resize(&msg->buf, attr_len))
1089                     return NULL;
1090           start = wpabuf_put(msg->buf, 0);
1091           wpabuf_put_u8(msg->buf, attr);
1092           wpabuf_put_u8(msg->buf, attr_len / 4);
1093           wpabuf_put_be16(msg->buf, value);
1094           if (data)
1095                     wpabuf_put_data(msg->buf, data, len);
1096           else
1097                     wpabuf_put(msg->buf, len);
1098           if (pad_len)
1099                     os_memset(wpabuf_put(msg->buf, pad_len), 0, pad_len);
1100           return start;
1101 }
1102 
1103 
eap_sim_msg_add_mac(struct eap_sim_msg * msg,u8 attr)1104 u8 * eap_sim_msg_add_mac(struct eap_sim_msg *msg, u8 attr)
1105 {
1106           u8 *pos = eap_sim_msg_add(msg, attr, 0, NULL, EAP_SIM_MAC_LEN);
1107           if (pos)
1108                     msg->mac = (pos - wpabuf_head_u8(msg->buf)) + 4;
1109           return pos;
1110 }
1111 
1112 
eap_sim_msg_add_encr_start(struct eap_sim_msg * msg,u8 attr_iv,u8 attr_encr)1113 int eap_sim_msg_add_encr_start(struct eap_sim_msg *msg, u8 attr_iv,
1114                                      u8 attr_encr)
1115 {
1116           u8 *pos = eap_sim_msg_add(msg, attr_iv, 0, NULL, EAP_SIM_IV_LEN);
1117           if (pos == NULL)
1118                     return -1;
1119           msg->iv = (pos - wpabuf_head_u8(msg->buf)) + 4;
1120           if (random_get_bytes(wpabuf_mhead_u8(msg->buf) + msg->iv,
1121                                    EAP_SIM_IV_LEN)) {
1122                     msg->iv = 0;
1123                     return -1;
1124           }
1125 
1126           pos = eap_sim_msg_add(msg, attr_encr, 0, NULL, 0);
1127           if (pos == NULL) {
1128                     msg->iv = 0;
1129                     return -1;
1130           }
1131           msg->encr = pos - wpabuf_head_u8(msg->buf);
1132 
1133           return 0;
1134 }
1135 
1136 
eap_sim_msg_add_encr_end(struct eap_sim_msg * msg,u8 * k_encr,int attr_pad)1137 int eap_sim_msg_add_encr_end(struct eap_sim_msg *msg, u8 *k_encr, int attr_pad)
1138 {
1139           size_t encr_len;
1140 
1141           if (msg == NULL || k_encr == NULL || msg->iv == 0 || msg->encr == 0)
1142                     return -1;
1143 
1144           encr_len = wpabuf_len(msg->buf) - msg->encr - 4;
1145           if (encr_len % 16) {
1146                     u8 *pos;
1147                     int pad_len = 16 - (encr_len % 16);
1148                     if (pad_len < 4) {
1149                               wpa_printf(MSG_WARNING, "EAP-SIM: "
1150                                            "eap_sim_msg_add_encr_end - invalid pad_len"
1151                                            " %d", pad_len);
1152                               return -1;
1153                     }
1154                     wpa_printf(MSG_DEBUG, "   *AT_PADDING");
1155                     pos = eap_sim_msg_add(msg, attr_pad, 0, NULL, pad_len - 4);
1156                     if (pos == NULL)
1157                               return -1;
1158                     os_memset(pos + 4, 0, pad_len - 4);
1159                     encr_len += pad_len;
1160           }
1161           wpa_printf(MSG_DEBUG, "   (AT_ENCR_DATA data len %lu)",
1162                        (unsigned long) encr_len);
1163           wpabuf_mhead_u8(msg->buf)[msg->encr + 1] = encr_len / 4 + 1;
1164           return aes_128_cbc_encrypt(k_encr, wpabuf_head_u8(msg->buf) + msg->iv,
1165                                            wpabuf_mhead_u8(msg->buf) + msg->encr + 4,
1166                                            encr_len);
1167 }
1168 
1169 
eap_sim_report_notification(void * msg_ctx,int notification,int aka)1170 void eap_sim_report_notification(void *msg_ctx, int notification, int aka)
1171 {
1172 #ifndef CONFIG_NO_STDOUT_DEBUG
1173           const char *type = aka ? "AKA" : "SIM";
1174 #endif /* CONFIG_NO_STDOUT_DEBUG */
1175 
1176           switch (notification) {
1177           case EAP_SIM_GENERAL_FAILURE_AFTER_AUTH:
1178                     wpa_printf(MSG_WARNING, "EAP-%s: General failure "
1179                                  "notification (after authentication)", type);
1180                     break;
1181           case EAP_SIM_TEMPORARILY_DENIED:
1182                     wpa_printf(MSG_WARNING, "EAP-%s: Failure notification: "
1183                                  "User has been temporarily denied access to the "
1184                                  "requested service", type);
1185                     break;
1186           case EAP_SIM_NOT_SUBSCRIBED:
1187                     wpa_printf(MSG_WARNING, "EAP-%s: Failure notification: "
1188                                  "User has not subscribed to the requested service",
1189                                  type);
1190                     break;
1191           case EAP_SIM_GENERAL_FAILURE_BEFORE_AUTH:
1192                     wpa_printf(MSG_WARNING, "EAP-%s: General failure "
1193                                  "notification (before authentication)", type);
1194                     break;
1195           case EAP_SIM_SUCCESS:
1196                     wpa_printf(MSG_INFO, "EAP-%s: Successful authentication "
1197                                  "notification", type);
1198                     break;
1199           default:
1200                     if (notification >= 32768) {
1201                               wpa_printf(MSG_INFO, "EAP-%s: Unrecognized "
1202                                            "non-failure notification %d",
1203                                            type, notification);
1204                     } else {
1205                               wpa_printf(MSG_WARNING, "EAP-%s: Unrecognized "
1206                                            "failure notification %d",
1207                                            type, notification);
1208                     }
1209           }
1210 }
1211 
1212 
eap_sim_anonymous_username(const u8 * id,size_t id_len)1213 int eap_sim_anonymous_username(const u8 *id, size_t id_len)
1214 {
1215           static const char *anonymous_id_prefix = "anonymous@";
1216           size_t anonymous_id_len = os_strlen(anonymous_id_prefix);
1217 
1218           if (id_len > anonymous_id_len &&
1219               os_memcmp(id, anonymous_id_prefix, anonymous_id_len) == 0)
1220                     return 1; /* 'anonymous@realm' */
1221 
1222           if (id_len > 1 && id[0] == '@')
1223                     return 1; /* '@realm' */
1224 
1225           return 0;
1226 }
1227